GRAND RAPIDS, MI -- As a child-abuse trial is wrapping up for a man accused of breaking at least 13 bones in his ex-girlfriend's baby, his attorney is suggesting the child's mother might be responsible for the injuries.

Testimony ended today in the trial of 25-year-old Andrew Pedro Valdez, charged with first-degree and second-degree child abuse for injuries to Bryson Devereaux.

Attorneys for both sides are expected to give closing arguments Friday, with the case going to the jury sometime in the morning.

Valdez is accused of breaking the 3-month-old baby's arm, leg and multiple ribs because he was upset that his then-girlfriend, Brooke Devereaux, was ordering him around. He was taking the baby out of a car seat at Devereaux's unit at York Creek Apartments in Alpine Township when police say the injuries happened on Oct. 19 or Oct. 20.

In a videotaped interview with Kent County sheriff's Detective Ed Kolakowski, shown to the jury today, Valdez initially denies doing anything wrong to the child.

But later, he admitted he "might have been too rough with him" and said the baby's leg did get caught in a strap on the car seat. He also admitted pulling the baby by the arm to get him out of the seat.

Valdez told the detective that he never thought the child was injured and never intended to hurt him.

"I was frustrated, but the anger wasn't toward him," he said. "I was frustrated with Brooke telling me to do this and that."

In testimony today, Kolakowski said he initially looked at the child's mother and Valdez as suspects in the abuse, but he ruled out the mother.

Defense attorney Damian Nunzio, in questioning both Kolakowski and Devereaux, seemed to suggest the mother could have caused the injuries.

He brought up an addiction to prescription medication she had in October and asked whether she handled the baby while she was high. She was taking drugs such as methadone and Vicodin and acknowledged she has tried to block out her child's injuries from her memory.

But Devereaux adamantly denied ever hurting the child.

"I could never do that to my son or daughter," she said.

Bryson's injuries, which included a bruise to his chin and ankle, were discovered by doctors at DeVos Children's Hospital on Oct. 20. Brooke Devereaux brought him there after her babysitter noticed something wrong with his leg and called Devereaux at her workplace.

Devereaux testified that Valdez thought she shouldn't go to the hospital. She had called him on the phone to tell him about the baby's problem.

"He had told me I was overreacting and that Bryson was fine and there was no need to take him in," she said.

If convicted of first-degree child abuse, Valdez could be sentenced to up to 15 years in prison.